Rotary field-motor



A. E. DU BOIS-RE'YMOND.

' ROTARY FIELD MOTOR.

No. 545,853. PatentedSe pt. 3,1895.

WITNESSES IN VEN T 0R WMMMW @W I ATTORNEY NITED STATES PATENT FfFICE.

ALARD E. DU BOISREYMOND, OF BERLIN, GERMANY, ASSIGNOR, IBY MESNEASSIGNMENTS, TO THE SIEMENS HALSKE ELECTRIC COMPANY OF AMERICA, OFCHICAGO, ILLINOIS.

ROTARY FIELDIMOTOR.

SPECIFICATION forming part of Letters Patent No. 545,853, datedSeptember 3, 1895.

Application filed December 26,1893. Serial No. 494,688. (No model.)Patented in Germany May 2'7, 1893, No. 68,411.

chines in general, and more particularly to the regulation of theeffective energy thereof,

irrespective of the current applied. If a number of rotarycurrent-motorsare to be operated in series, orif a rotary current-motor is to beoperated with varying effective energy, but with a constant strength ofcurrent, the question of the most advantageous method of changing thetension of the current at the terminals of the motor from zero to itsmaximum value arises. The usual means employed to attain this objectwhen operating a system of constant tension is to introduce resistanceinto the working circuits. This, however, cannot be done in the presentinstance, for the reason that the potentials at the terminals of themotor would not be affected thereby.

This my present invention consists in the method and means forregulating a rotary 'currentmachine through the alterations in thelengths of the windings thereof, irrespective of the currenttransmitted, by dividing each of the several windings of the fixedmember thereof into a series of separate sections having the desirednumbers of convolutions,

their adjacent ends being electrically connected by means ofcontact-strips arranged to be borne against by contacts in electricalrelation to the working conductors of a distributing system, the saidcontacts having means whereby they may be shifted relative to the saidstrips.

In the accompanying drawings, forming a part of this specification, andin which similar letters of reference indicate like parts in the severalfigures thereof, Figure l is a diagrammatical representation of thefixedmenrber of a three-coil machine and its regulating mechanism as itmay be arranged in accordtime with my invention. Fig. 2 is a similarrepresentation of a machine in which twelve coils are used.

Referring now to the drawings, and more particularly to Fig. 1 thereof,which shows my invention as applied to a three-coil motor, A representsthe fixed member of a machine having its windings, consisting of threecoils B B B, each involving a number of individual coils b b 1)",arranged in series, the adjacent ends of each-pair of coils beingconnected through the medium of a fixed contact piece or strip 0,arranged conveniently to the said member in such a position as to beborne against by brushes d d 01", having electrical connection withtheir respective feeder-conductors F F F.

In the drawings I have shown the several brushes d d d" as attached to acommon insulated carrier e, arranged concentrically with the machine,the contact-strips being secured directly to and transversely of thefixed member A of the machine. As shown, the carrier is of such diameteras to enable the use of the usual brushes and the adjustment thereof tocompensate for wear, the said carrier being pivotally hung. A lever orsuitable gearing automatically or manually operated may be arranged toshift the carrier, and thereby to transmit to the brushes thereon amovement peripherally relative to the fixed member of the machine, thusvarying the lengths of windings of the said member through the medium of'the contact-strips. It will thus be readily seen that by shifting thebrushes from what may be termed the zero points f, f, and f,respectively, in a direction to traverse their respective segments B, B,and B of the fixed member of the machine a greater number ofoonvolutions may be included in the circuit of the windings of themachine as each successive contact-strip c is borne against by itsbrush, with the result that the efiiciency of the machine is increaseduntil the final strips h, h, and h are reached, when by reversing.themovement of the shifting mechanism the successive convolute sections ofthe winding may be removed from the circuit, and thus their energizingeffect will be annihilated.

In Fig. 2 of the drawings I have shown this same principle as applied toa twelve-coil ma chine. It is evident to those skilled in the art thatthis my invention may be applied to a dynamoqnachine as Well as to amotor, and that the particular form of the brush-carrier, as well as itsshifting mechanism, maybe altered at will Without departing in anymanner from the spirit of my invention.

A very desirable carrier may be constructed in the form of a star andarranged concentrically with the machine, the brushes being secured to aseries of bars arranged perpendicularly to the arms of the said star andextending to inclose the machine.

1. In a rotary current motor the combination with a number of coils eachconnected at intermediate points With a number of contact terminals,said contact terminals being arranged in a circle, of a number ofbrushes, one for each coil, mounted to be moved over said terminals andadapted to make contact With corresponding terminals of the severalcoils whereby the effective lengths of the several coils may be variedat Will, substantially as described.

2. In a rotary current motor, the combination with a ring member Woundwith a number of coils, of a series of contact terminals connected witheach of said coils at interme diate points, said contact terminals beingarranged in a circle, and brushes or contact devices mounted in fixedrelative positions and adapted to be moved over said terminals to makecontact with the corresponding tel minals of the several coils wherebythe lengths of the respective terminals may be varied, substantially asdescribed.

In testimony whereof I affix my signature in the presence of twowitnesses.

ALARD E. DU BOIS-REYMOND.

Witnesses:

OSCAR BIELEFELD, JOHN B. JACKSON.

